Fall is almost in the books, or at least it is meteorologically speaking. We break the seasons down into three month intervals for book keeping purposes and we’re about to enter the 3 month period we look at as meteorological winter (December through February). So it’s time to break out the annual WYMT Winter Forecast.
This year’s forecast was extremely difficult to put together. The fact of the matter is seasonal forecasting is always difficult, and some factors this year are making it even harder than normal to forecast for the entire winter. Before we get to that, let’s take a look at what a “typical winter” should look like in Eastern Kentucky.
First off let’s talk temperatures. At the National Weather Service office in Jackson the average temperature through the winter is 37.2 degrees, and at the London-Corbin Airport it’s just slightly higher at 37.8 degrees. Now that average temperatures is developed from taking the highs and lows of every single day of the winter and averaging them together. January is typically our coldest month of the year; in fact the coldest January on record at Jackson happened in 1985 when the temperature averaged just 24.5 degrees.
Now to the part people love and hate, how much snow do we “typically” see in an Eastern Kentucky winter? Our friends at the National Weather Service in Jackson have put together a great map that illustrates how much snow we see. You can see above. As you can see, most of Eastern Kentucky averages 8-12”s of the white stuff, while the higher elevations of Breathitt, Perry, Pike, Knott, Floyd, Letcher, Harlan, and Leslie counties gets about 12-18”s. The big winners for snow as always are the mountains of Pike, Letcher and Harlan counties which generally average 2-3’ of snow per winter. The snowiest winter on record at the Weather Service Office in Jackson was in 1995-96 where they picked up 62.7”s (This includes snow from the entire snow season October through April).
So now that you know what an average winter looks like across the coalfields and mountains of Eastern Kentucky, let’s take a look at what the big driving force behind this year’s winter pattern will be. The biggest factor we typically look at is the temperature in the Pacific Ocean, better known as La Nina or El Nino. La Nina is a cooling in the southern Pacific, while El Nino is a warming pattern. Well this year we actually have neither, or what we call La Nada. This is part of what makes the forecast this year so difficult is the big driving factor just simply isn’t there, and we are going to be steered by smaller scale, and harder to predict factors. One thing we will note however is; compared to the last two years there is more ice in the Arctic Circle and the snow pack across Canada is more expansive. This would give us more cold air to work with than we had the last two years, which featured both above average temperatures, and below average snow.
On to the forecast! We’re going to break it down month by month for you. We start off in December which should start off colder than normal as a big trough looks to set up shop in the Mississippi and Ohio River Valleys. A trough is a dip in the jet stream (that river of air in the upper atmosphere that guides our weather patterns) that allows colder air to come on down. This will also give us a few shots at some early winter snows from some quick moving Alberta Clipper style storm systems. Those are the fast moving cold fronts that can often bring us light snow in the winter. During the second half of December I see that trough pulling back to the north and some warmer air will roll into Kentucky. Since we’re splitting the month in half, we’re going to go with temperatures in the average range of 37-39 degrees and average snow of around 4-6”s. At little less can be expected in the Cumberland Valley, with more in the Mountains of Pike, Letcher and Harlan Counties.
January is up next, and this one could be a cold one. With the arctic sea ice on the increase, as well as the snow pack in Canada already beefed up, we could see a lot of cold air off to our north compared to the last two years. There’s a good shot that during this month that cold air is going to get pushed down into the lower 48 several times, and there could be some prolonged cold stretches during this month. Temperature wise I think we could end up as much as 2-3 degrees cooler than average, putting the average temperature range down to 30-32 degrees. Snow in this kind of setup can be hard to predict because if the cold pushes too far south, it can move the storm track farther south and get us out of the best storm path for snow. As of now we’re going to go slightly above average snow for January, in the 7-9” range, with less in the Cumberland Valley, and more in the higher elevations.
Now on to February, and this is where the forecast is going to get very tricky. Remember how we are in a La Nada right now; meaning the southern Pacific is at average water temperatures? Well some of the computer models we use to forecast are showing it warming around this point, and others are keeping it around normal. Looking at other years with similar weather patterns, it looks like the chance of it warming up and going into a weak El Nino are certainly possible. If this happens, we should see the subtropical jet stream kick into gear, and start ushering in some warmer and moister air into the southeast. We could even see a strong area of high pressure develop over the south east that would re-enforce the chance of warmer air coming into the region. Because of that, we’re going with a warmer than average February with the temperature range averaging 38-40 degrees. Also this would at least hint at a lower than average snowfall for the month, we’re going to go with a general 4-7”s.
Now when all that gets factored together, that would mean we’re looking at a pretty “average” winter. We will have to see how it all plays out, and a lot about this forecast is very low confidence. The big things to watch for are late season can we get that moisture we’re expecting to crank in to meet up with some cold air. If it can, look out! That can cause some big time winter storms in the eastern half of the US. The other thing with this kind of set up is be on the lookout for the potential of some early year severe weather and ice storms threats. I would say our chances of both are slightly above average, especially in February and March. One last thing, one big snowstorm can completely shoot this forecast in the foot. Hope you have enjoyed this year’s winter forecast, and keep tuning into WYMT-TV as we track all the weather across Southern and Eastern Kentucky!